<template>
  <div>
    <div class="shopcart">
      <div class="content" @click="toggleList">
        <div class="content-left">
          <div class="logo-wrapper">
            <div class="logo" :class="{'highlight': totalCount > 0}">
              <i class="icon-shopping_cart"></i>
            </div>
            <div class="num" v-show="totalCount > 0">{{totalCount}}</div>
          </div>
          <div class="price" :class="{'highlight': totalPrice > 0}">￥{{totalPrice}}</div>
          <div class="desc">另需配送费￥{{deliveryPrice}}元</div>
        </div>
        <div class="content-right" @click.stop="pay">
          <div class="pay" :class="payClass">{{payDesc}}</div>
        </div>
      </div>
      <div class="ball-container">
        <transition name="drop" v-for="(ball,index) in balls" :key="index" @before-enter="beforeEnter" @enter="enter" @after-enter="afterEnter" :css="false">
          <div v-show="ball.show" class="ball"></div>
        </transition>
      </div>
      <transition name="fold">
        <div class="shopcart-list" v-show="listShow">
          <div class="list-header">
            <div class="title">购物车</div>
            <div class="empty" @click="empty">清空</div>
          </div>
          <div class="list-content" ref="listContent">
            <ul>
              <li class="food" v-for="(food,index) in selectFoods" :key="index">
                <span class="name">{{food.name}}</span>
                <div class="price">
                  <span>￥{{food.price * food.count}}</span>
                </div>
                <div class="cartcontrol-wrapper">
                  <cartcontrol :food="food"></cartcontrol>
                </div>
              </li>
            </ul>
          </div>
        </div>
      </transition>
    </div>
    <transition name="mask-fade">
      <div class="list-mask" v-show="listShow" @click="hideList"></div>
    </transition>
  </div>
</template>
<script>

import BScroll from 'better-scroll'
import Cartcontrol from '../cartcontrol/cartcontrol'

export default {
  components: {Cartcontrol},
  data () {
    return {
      balls: [
        {
          show: false
        },
        {
          show: false
        },
        {
          show: false
        },
        {
          show: false
        },
        {
          show: false
        }
      ],
      dropBalls: [],
      fold: false
    }
  },
  props: {
    selectFoods: {
      type: Array,
      default () {
        return [
          {
            price: 10,
            count: 1
          }
        ]
      }
    },
    deliveryPrice: {
      type: Number,
      default: 0
    },
    minPrice: {
      type: Number,
      default: 0
    }
  },
  methods: {
    drop (el) {
      for (let i = 0; i < this.balls.length; i++) {
        let ball = this.balls[i]
        if (!ball.show) {
          ball.show = true
          ball.el = el
          this.dropBalls.push(ball)
          return
        }
      }
    },
    toggleList () {
      if (!this.totalCount) {
        return
      }
      this.fold = !this.fold
    },
    hideList () {
      this.fold = true
    },
    empty () {
      this.selectFoods.forEach((food) => {
        food.count = 0
      })
    },
    pay () {
      if (this.totalPrice < this.minPrice) {
        return
      }
      window.alert(`需要支付${this.totalPrice}元`)
    },
    beforeEnter (el) {
      let count = this.balls.length
      while (count--) {
        let ball = this.balls[count]
        if (ball.show) {
          let rect = ball.el.getBoundingClientRect()
          let x = rect.left - 32 + 10
          let y = -(window.innerHeight - rect.top - 22 - 16 - 8)
          el.style.display = ''
          el.style.transform = `translate3d(${x}px, ${y}px, 0)`
        }
      }
    },
    enter (el, done) {
      /* eslint-disable no-unused-vars */
      let rf = el.offsetHeight
      this.$nextTick(() => {
        el.style.transition = 'all .4s'
        el.style.transform = 'translate3d(0, 0, 0)'
      })
      setTimeout(function () {
        done()
      }, 400)
    },
    afterEnter (el) {
      let ball = this.dropBalls.shift()
      if (ball) {
        ball.show = false
        el.style.display = 'none'
      }
    }
  },
  computed: {
    totalPrice () {
      let total = 0
      this.selectFoods.forEach((food) => {
        total += food.price * food.count
      })
      return total
    },
    totalCount () {
      let count = 0
      this.selectFoods.forEach((food) => {
        count += food.count
      })
      return count
    },
    payDesc () {
      if (this.totalPrice === 0) {
        return `￥${this.minPrice}元起送`
      } else if (this.totalPrice < this.minPrice) {
        let diff = this.minPrice - this.totalPrice
        return `还差￥${diff}元`
      } else {
        return '去结算'
      }
    },
    payClass () {
      if (this.totalPrice < this.minPrice) {
        return 'not-enough'
      } else {
        return 'enough'
      }
    },
    listShow () {
      let me = this
      if (!this.totalCount) {
        me.fold = true
        return false
      }
      let show = !this.fold
      if (show) {
        this.$nextTick(() => {
          if (!this.scroll) {
            me.scroll = new BScroll(this.$refs.listContent, {
              click: true
            })
          } else {
            this.scroll.refresh()
          }
        })
      }
      return show
    }
  }
}
</script>

<style scoped lang="stylus" rel="stylesheet/stylus">
  @import "../../common/stylus/mixin.styl"
  .shopcart
    position fixed
    left 0
    bottom: 0
    z-index 40
    width: 100%
    height 48px
    .content
      display flex
      background #141d27
      font-size 0
      color rgba(255,255,255,.4)
      .content-left
        flex 1
        .logo-wrapper
          display inline-block
          vertical-align top
          position relative
          top -10px
          margin 0 12px
          padding 6px
          width: 56px
          height: 56px
          box-sizing border-box
          border-radius 50%
          background #141d27
          .logo
            width: 100%
            height: 100%
            border-radius 50%
            background #2b343c
            text-align center
            &.highlight
              background rgb(0,160,220)
            .icon-shopping_cart
              line-height 44px
              font-size 24px
              color #80858a
              &.highlight
                color #FFFFFF
          .num
            position absolute
            top: 0
            right: 0
            width: 24px
            height: 16px
            line-height 16px
            text-align center
            border-radius 16px
            font-size 9px
            font-weight 700
            color #FFFFFF
            background rgb(240, 20, 20)
            box-shadow 0 4px 8px 0 rgba(0,0,0,.4)
        .price
          display inline-block
          vertical-align top
          margin-top 12px
          padding-right: 12px
          line-height 24px
          box-sizing border-box
          border-right 1px solid rgba(255,255,255,.1)
          font-size 16px
          font-weight 700px
          &.highlight
            color #fff
        .desc
          display inline-block
          vertical-align top
          margin: 12px 0 0 12px
          line-height 24px
          font-size 10px
      .content-right
        flex 0 0 105px
        width 105px
        .pay
          height 48px
          line-height 48px
          text-align center
          font-size 12px
          font-weight 700px
          &.not-enough
            background #2b333b
          &.enough
            background #00b43c
            color #fff
    .ball-container
      .ball
        position fixed
        left 32px
        bottom 22px
        z-index 10
        width 16px
        height 16px
        border-radius 50%
        background rgb(0,160,220)
    .fold-enter-active,.fold-leave-active
      transition all 0.5s ease
    /* .fold-leave-active for below version 2.1.8 */
    .fold-enter,.fold-leave-to
      transform translate3d(0,100%,0)
    .shopcart-list
      position absolute
      left 0
      bottom 100%
      z-index -1
      width 100%
    .list-header
      height 40px
      line-height 40px
      padding 0 18px
      background #f3f5f7
      border-bottom 1px solid rgba(7,17,27,.1)
      .title
        float left
        font-size 14px
        color rgb(7,17,27)
      .empty
        float right
        font-size 12px
        color rgb(0,160,220)
    .list-content
      padding 0 18px
      max-height 217px
      overflow hidden
      background #fff
      .food
        position relative
        padding 12px 0
        box-sizing border-box
        border-1px(rgba(7,17,27,.1))
        .name
          line-height 24px
          font-size 14px
          color  rgb(7,17,27)
        .price
          position absolute
          right 90px
          bottom 12px
          line-height 24px
          font-size 14px
          font-weight 700
          color rgb(240,20,20)
        .cartcontrol-wrapper
          position absolute
          right 0
          bottom 6px
  .list-mask
    position fixed
    top 0
    left 0
    width 100%
    height 100%
    z-index 20
    backdrop-filter blur(5px)
    background rgba(7,17,27,0.3)
  .mask-fade-enter-active,.mask-fade-leave-active
    transition all .5s
  /* .mask-fade-leave-active for below version 2.1.8 */
  .mask-fade-enter,.mask-fade-leave-to
    opacity 0
</style>
